Combined alternating and direct current distributing system.



.I. H. GUGLER & G. W. COLLES. COMBINED ALTERNATING AND DIRECT CURRENT DISTRIBUTING SYSTEM.

APPLICATION FILED FEB. 8 1911.

6 l 1 11 T 55 mm 10% MWB nv b a P J. H. GUGLER & G. W. CQLLES. COMBINED ALTERNATING AND DIRECT CURRENT DISTRIBUTING SYSTEM.

I APPLICATION FILED FEB. 8. I911- 1,169,537. Patented Jan. 25, 1916.

3 SHEETSe-SHEET 2.

J a! Q I J a V J P a IIIIIIIIIIIIIIIII 2 t y I l I Z I. H. GUGLER & G. W. COLLES.

COMBINED ALTERNATING AND DIRECT CURRENT DISTRIBUTING SYSTEM.

APPLICATION FILED FEB.8I19H.

Patented Jan. 25, 1916.

3 SHEETS-SHEET 3.

sraTEs ra'rsnr c rries.

JULIUS H. enema AND GEORGE W. CULLES, or MILWAUKEE, WISCONSIN; sen) COLLES AssIGNon T0 SAID G-UGLER. a

CGMBINED ALTERNATING AND DIRECT CURRENT DISTRIBUTING SYSTEM.

menses.

T0 allwlwm it may concern:

Be it known that we, JULIUS H. GUGLER and GEORGE W. CoLLEs, of Milwaukee, lVisconsin, have invented a'Combined Alternating and Direct Current Distributing System, of which the following is al specification. i

This invention, relates more particularly to line-service served by an alternating-current circuit during. most of the time, and provided with a storage-battery to be used during the remainder of the time; and it has for its object to provide means for automatically causing the direct current to be turned on to the lighting-system whenever the alternating-current is discontinued, and

turned ofl'v again when the alternating-coir rent is turned on. without manual attention. In many smallv towns and villages, especially those where service is to individual houses widely scattered. the high-tension alternating-c1urent distribution is used, the current being provided direct from a generator. In such systems the amount. of currentused during the night is so smallthat it does not pay to keep the generator running all night to accommodate it. In order now to provide 24-hour service upon such systems without the necessity of keeping the station running all night, a storagebattery is provided at the station, anda direct-current line-circuit leading therefrom in addition and parallel to the alternating current circuit from the generator. As the amount ofcurrent required during the hours in which the storage-battery is usedis very small. the line .loss is negligible for this period even for long distances. Branch--.

circuit wires are run from the direct-current circuit to the individual house-systems, or wherever there isa transformer providing for such ,a branch-system; and it is in such case necessary to provide means for switch- 'alternatirig-current circuit. a In general we provide an electromagnetic ing on the direct-current whenever the altermat ng-current 1s off,.and such means must be SQdQVlSQd that n no case can both systerns be turnedon the service wires at once.

It is the object of this. invention to provide suchmeans, and moreover to provide. for performing the switching-act on auto? matic'ally as hereinab ove stated, theactuating force for the switch proceeding from the device which is actuated directly or indirectly from the secondary of each trans- Specificatmn of Letters Patent.

- notes an alternating-current Patented J an. 25, 1916.

'Application fiIed FebruaryS, 1911. Serial No. 607,323.

former, said electromagnetic device' being caused to be energized whenever there is an electromotive force applied .to the transformer, and thereby to move the change over-sw1tch to the alternatmg-crrrent side; and conversely ,when current ceases 1n the transformer-secondary, to move said switch to the opposite or direct-current side. In a more improved form of our invention we provide further interlocking-means to prevent any short-circuit which would occur were some of the electromagnetic-devices to fail to act; in case the branch lighting-system should be connected together as is customary for purposes of regulation.

Further improvements and combinations 7 will be hereinafter described and detailed, and are particularly set forth in our claims. For the better understanding of our invention, we have illustrated in the accompanying drawings several embodiments of our'm-vention, some being more improved and elaborate than others; and in these drawings Figure 1 is a diagram of a complete alternating-current lighting-system having three branches and showing the sim "plest form of our automatic switching de" vices; Fig. 2 is a similar viewwviththe addition of a. simpleinterlocking-device;

Fig.3 shows a systemprovided with an im-' proved form of interlocking device and a difierent form of electromagnetic-switch;

Fig. 4 illustrates an alternative form operating on the same principles as that shown in Fig- 3; Fig. 5 illustrates a system in which -the general arrangement and elements are the same as in Fig. 4, but the interlockingdevices are connected in parallel instead of in series; and Flg. .6. lllustrates especially may be maintained in its raised position 'withoutthe/necessityof keeping it energized; and showing also further improvements in the interlocking-devices whereby thepositive operation of each interlocking device individually is insured.

The reference letters refer .'each to the same part in each figure of t e drawings.

Considering firstFig' 1, the letter A deenera'tor supa means whereby-the electromagnetic-switch direct current dynamo attachedto the gen-' erator A, and representedherein by a commutator C, from which direct current 1s taken by the leads a in the usual manner. At various places along the line transformers Tare-installed, the soil it representing the primary coil, and the coil t the-.sec ondary coil of'each of. said transformers;

The lighting-systems L which, carry the lights Z, andYwhich in this 1 case are shown disconnected from each other, are served alternatively from the circuit 6 or the transformer-secondary t as will be presently seen. To this end a'common wire 11 isrun' from one of the wires 6 (the same wire for each of the branch lighting-circuits) and permanently'connected to one side of the cor-' responding.lighting-system, and one side of the transformer-secondary t connected thereto by a'wire 12. A third Wire 13 is run from the other line-wire b to one terminal 8 of the changeover-switch S, and a fourth wire 14; is run' from the other side of the secondary t to the opposite terminal .9 ofthe switch. Theside of the lighting-system L opposite that to which the wire 11 is connected is. permanently connected by a lead 15 to the switch-blade 8 so that this side of the lighting-system may be connected either.

with the direct-current or alternating-current circuit according to its position. The

'- switch S is actuated by the armature eof an electromag'net or solenoid E, being con-' nected thereto by a link 0 or othersuitable mechanical connection. .The 1electromagnet or solenoid E is as shown connected directly across the terminals of the secondary t of the transformerso. that whenever the alternating-current comes into the secondary, the electromagnet E is'energized and raises its armature and switch-blade s and moves the latter into the dotted-line position, whereby the lighting-circuit L is connected to and supplied from the transformer. This condition .will remain as long as there is an alternating-current on ;the line, and when it is discontinued the electromagnet E being no longer energized will drop its core and thereby throw over the switch S to the direct-current side, so thateach branch light-- ing-system is now supplied with current from the battery B. If the parts are all in good working order, the change wilt of course takesplace on all the branch-circuits at once. 1

In Fig. 1 the branch lightingsystems are shown as disconnected from each other; but it is customary for better regulation and economy of transformer capacity to connectthe secondariesof neighboring circuits together. Should this be done, and should the apparatus. be as shown in Fig. 1, then if anv derangement occurs to one of the electrdmagnetic-switches, so that it fails to act, and one or more of the othersdo act, there will be a short-circuit of the direct-current circuitthrough one or more of the transformersecondaries. To prevent this from taking place, we introduce an interlocking-system between the several electromagnetic switches, p

a simple form of which is illustrated in Fig. 2. In this figure the construction is as already described in Fig. 1 with thefollowing additions: The lighting circuits L are connected together. by line-wires 20. pivoted bar 1* is connected to the link 0 its end extending beyond the latter, and being in position for engagement with a .trip g on the end of a trip-lever G, upon which is mounted the armature g of an electromagnet or solenoid H. The bar F and lever .G are of electrically conducting ma-;

terial, and the bars F, levers 'G,'and elec-" tromagnets H, of. all the interlocking-dc vices are.so connected together that when the bars F are in contact with their.=re,-

spective levers G, theyare all'in series and" in circuit across the battery-mains. I In other. Words, the bar F of the interlocking-device at one end of theseries-is permanently "con current circuit, asto the lead 11;-:=the]cornected by a lead.16 to one side of the direct.f

respondingv lever G is connected by a lead-i .17 to one terminal ofthe corresponding" elecfi 5 tromag'netor solenoid'H; theother terminal-. .of the latteris connected by a lead 18 tothe bar F of the next interlocking-device in the series; andso'on until the lastone is reached,

the terminaleof thellast electromagnet H being connected directly tothe opposite side of the battery, as for example to the lead13; The arrangement offtheend of; the bar F in relation to the trip'g' is such that the two can be in contact only when the switch-lever s is out of contact with both the electrodes 1 any one of theelectromagnets E fail to act,

the bar F- belonging to that'electromagnet will not come into contact with its corre ending trip-lever G, and thereby the inter ocking-circuit will not be completed, and, therefore none of the switches S can be thrown, and therefore the short circuit her-e llinabove indicated cannot take placer This will be the case, no matter whether the throw is in the upward or the downward direction.

While the arrangementjust described provides agai'nst'an immediate short-circuit due to failure of one of the electromagneticdevices E to act, yet another contingency is introduced through the possible failure withdraw intime to release the corresponding bar F. In this case the bar F of the interlocking device so failing to'act would of course be held either by gravity or by attraction of the electromagnet E against the trip 9 and for the time being there would be no short-circuit, but the lights on that branch would be out off. If this is discovered and remedied before a reversechange' fromalternating to direct or direct to alternating takes place all will be well, but if not discovered or remedied before such reverse-change takes place, then when said reverse change takes place, the switchlever S of the branch where the interlock has failed to act will immediately drop back to its original position without regard to the. interlock, and all the other switches will be held by the trips because the interlocking-circuit cannot be closed; and this will therefore throw all the other branches out of service, or should any of the electromagnetic switches of said branches fail to operate, it will remain on the o posite side from-the one where the interloc has failed to operate, and thus cause a short-circuit.-

is shown in motor-form with a shuttlewound cylindrical armature 6 adapted to rotate through a certain angle suflicient to operate the switch S, which consists of a contact-member .9 adapted to close the circuit between the terminals s and s, or s and 8 The terminals 8 and s are connected by a lead 21' to one side ofthe lamp-circuit L; one side of the transformer-secondaryand one side of the battery-circuit are connected by a common lead 22 to the other side of the lamp-circuit L, the other side of the transformer-secondary is connected by a lead 23 to terminal 8 and the other side of the batteryis connected by a lead 24 to the terminals 8. The electromagneticdevice E is connected by a circuit compris' ing the leads 25, 26 and 27 across the battery-circuit, but between the leads 26 and 27 is interposed a make-and-break device I operated by an electromagnetic-device i, which is connected across the terminalsof the secondary transformer circuit as shown.

This arrangement is more etiicient than that locked.

thus connecting the terminals 8 and s, and

closing the lamp-circuit through the transformer-secondary. When the alternatingcurrent goes off, the make-and-break I is opened, the electromagnetic-device E releases its armature, and the latter is turned by a counter-balance 6* into the opposite position, closing the lamp-circuit across the direct-current circuit through the terminals 8" and s. The interlocking-device comprises the bar F which turns with the armature 6 the locking-piece G, which has a central notch g of proper form to fit over the end ofthe bar F; and an electromagnet H. The locking-piece G acts as the armature of the electromagnet H and also as the 1 contact-piece to make electric contact with the bar F, and it has oblique cam-faces g on its sides whereby the end of the bar F raises it as said bar swings over,

and thus the bar becomes caught and locked in the notch 9 In this position it cannot move in either direction until the magnet H" is energized, so as to withdraw the locking-piece G from engagement therewith. The connections by which this is performed are the same as before, to wit: a lead 28 permanently connecting one side of the battery-circuit with the first bar F of the series; a lead'29 connecting the armature G with the electroinagnet H; a lead 30 connectingthe latter with the next bar F of the series; and so on to the last electromagnet H, which is connected by, a lead'31 to the other terminal of the-battery-circuit.

vFrom this arrangement it'will be clear that when a change takes place from alternating to direct-current or vice versa, all of the electromagnetic switches whlch are in work- 'ing order will swing over until they are caught and retained by the locking-pieces G; If any electromagnetic switch is out of order or fails-to act; they will move no farther than this until the defect is remedied; and should any of the electromagnetic-locks fail to act, the corresponding switch will be held in its middle position'until after the reverse-change has taken place, and all of the other switches have again become Therefore with this devicea shortcircuit caused by the failure of the switches toblwork together will be practically imposs1 e. a

An alternative form of this construction is shown in Fig. 4. in which the direct and alternating-current circuits a and I), the lamp circuits. L, the transformer T, and the connections designated by the same referencenumbers are unchanged, but a form of electromagnet E having a vertically mov- -ing armature 6 similar to those shown in Figs. 1 and 2 is used. Said electromagnet E is connected across the direct-current circuit by the connections 25, 26 and 27 as before, but instead of the make-and-break I closing the circuit when attracted by the magnet z, a make-and-breakl' is used which opens when attractedby its magnet i and closes when released. A different form of switch S is substituted, said switch comprising atransverse contact-bar s mounted on the lower end of the reciprocating-post e which is secured to the armature e and guided to move vertically; and'the four terminals 8 s, s and 8,, the last two of which are connected together and to the lamp-circuit on the opposite side from the lead 22 by a lead 32. The terminals 8 s .are connected respectively to thealternating-secondary and direct-current circuits by the leads 23 and24. It will be obvious that the lower position of the armature e 'and switch-bar 8 corresponds to the alternating, and the upper position to the direct-current connection of the lamp-circuit; so that the energized condition of the device E cor'responds in this case to the period during which direct current is supplied to the lampcircuit. The interlockingdevice is here con structed as follows :A sliding bolt or locking-piece G is mounted to reciprocate in a line at right angles to the post e, and is caused by. means of a spring 9 to bear against the latter, and to enter a notch c in the side of the post when it is in its central position. The armature g of the releasingmagnet H is mounted on this bolt in a position to withdraw it'from the notch 13 when said magnet is energized, and said armature 9 acts as a connecting-piece to electrically connect the terminals 9 51*v when the bolt is in its forward position, and to disconnect said terminals when it is drawn back. The lead 28 connects one pole of the battery-circuit to the terminal 9 of the interlockingdevice at one end of the series. and the lead 29 connects theother terminal to one pole of the magnet H; the other terminal of said magnet is connected by the lead 30 to the terminal g of the next interlockingdevice; and so on to the last one, the magnet H of which is connected by the lead 31 to the other terminal of the battery, thus forming the same series-counection of the interlocking-device as hereinabove described. It will be seen that as the switches are thrown over by the action of the electromagnetic devices E, thev are locked as they reach their central position by the entrance of the bolts G into the notches (2 thereof, and none of them can be unlocked until all of them are in said notches, at which time they are simultaneously unlocked; and in every respect the action the same as in Fig. 3.

when so connected.

the interlocking-devices as contrasted with the series-connection of Figs. 2, 3 and 4.

The terminals and g which are nor- .mally disconnected and become connected by the locking-movement of the bolt, are in this case replaced by terminals g, g, which are so placed as to be normally connected together, and they are disposed so as to short-circuit the respective magnets H" The latter are not connected in series, but one terminal of each is connected directly by a lead 33 to one side of the battery-circuit, as for example to the lead 24, and the other terminal of each is connected to a lead. 3% which extends through all of the interlocking-devices of the series, and is connected at some point through a resistance R with the otherpole of the battery-circuit, as for example to the lead 22. It will: be seen that so long as any of the bolts G- are withdrawn, all of the releasing-magnets H are short-circuited through the terminals g g and armature g of that one which is withdrawn, and therefore that only when all of them are thrown forward'do the magnets H become energized. The resistance R is inserted to prevent short-circuiting of the battery-circuit. This method while practicable is con,- sidered in general less useful than the seriesconnectio'n since it involves the continual use of some current to support the interlocking-devices, but it may be preferable in certain cases. 1

In the most improved form' of our apparatus, shown in Fig. (3, we have aimed to obviate two disadvantages inherent in the apparatus as thus-far described, though involvmg greater complexity. It may be obvious that 1n the forms of Figs. 2, 3, 4 and 5 continual use of the battery will be necessary in order to hold the switches in their alternating-current position, and should the battery be cut out, all the switches wouldgo over to the direct-current side and the lights would be shut off. Moreover, there will be considerable waste of battery-current, assuming that the alternating-current is to be used for 12 to 18 hours a day. To avoid this we provide 'an automaticcatcli to sustain the switch in number of switches are on the circuit, one or more of them will fail to act at each reversal of the switch. .To avoid thiswe provide means whereby the interlocking-devices are actuated for withdrawal individually and independently from supplementary circuits which are only closed by the interlocking-circuit and are opened by their own automatic action in withdrawing the lockingbolts. This improved device is also illustrated in Fig. 6. lVe have shown the two apparatuses of Fig. 6 in different positions, not because they would'naturally be so, but in order to illustrate the two positions. The parts which are repeated without alteration from Figs. 4 and 5 are designated by the same reference-letters. On the left of Fig. 6 the place of the make-and-break I and magnet z' is taken by a magnet 2' connected in shunt across the secondary of the transformer T by leads 35 and 36, and its two movablearmatures i and 77* both weighted to stand normally apart from the magnet, and adapted to make contacts, the former when it is closed with a terminal i the latter when it is opened with a terminal *5.

The two make-and-breaks formed by the elements 2', i and 2', i are interc'alated in series in the circuit of the electromagnetic-device E; the course of the current, starting from the battery-lead 22, being through the lead 12, armature i", terminal 2', lead 37, armature 2', terminal 2', lead 38, electromagnetic-device E", and lead 25 to the opposite battery-lead 24. The device is completed bya lock-lever J, pivoted at j, and connected by a link j" to the armature i The free end of the lever J is adapted to engage in a notch in the side of the post 6, which notch is so placed as to register with the end of the lever J when the post is in its raised position. The mode of operation is as follows: \V hen the alternating-current is turned on to the transformer T, the switch S being down, the magnet i is energized and thereby attracts the armature i, closing the break at The break at i is not opened because the armature i cannot be moved until the post 6 hasbeen raised, by reason of the engagement ofthe lever J with the side of the post a. T he circuit of the electromagnet E is therefore closed, the latter energized so Lure 6", and the weight thereof disengages it to raise its armature i This condition of.

the lever J from the notch e permitting the post 6 to fall. At the same moment the circuit of the electromagnet E is opened at 6 thus preventing the re'energizing of the same.

A different form of this device with only one armature is shown on the right of Fig. 6. In this case the magnet iwhich replaces the magnet 2' has only one armature 2", which is mounted on the end of a rod i the latter carrying or operating at its lower end a contact piece i Inv this case the lever J, which replaces the lever J, is used as a conducting-element to connect electrically the contact-piece 2' with a terminal i, but as will be seen both i and 2' are not simultaneously in contact with the lever J under normal circumstances. The devices i, i and J are intercalated in the energizing-circuit of the electromagnetic-decurrent is shut off, the contact-piece 01 is below and out of contact with the lever J, consequently the energizing-circuit remains open until the alternating-current is turned on, which energizes the magnet i and causes At this time the energizing-circuit of the electromagneticdevice E is closed because the lever J is held in contact with the terminal i until the rising of the post 6 to the top permits the end of said lever to engage with the notch 6 at which moment the energizing circuit is broken at i, and. the postc mechanically sustained as heretofore described. When the alternating-current is turned off, the armature i drops, releasing the lever J from engagemenet with the post a, and

breaking the energizing-circuit at 2' .Our

31, the same as hereinabovedescribed, in

which interlocking-circuit are also inserted in series the several interlocking-unignets H. TheseinteHocking-magnets operate upon independent armatures m which are .mounted on reciprocating bolts M, and

carry each a contact-piece m which is 'adaptedto unite two terminals on, m disposed in the circuit 40, ll and 42 of the magnet K, saidcircuit connecting each of said magnets K individually across the battery-circuit. The two bolts G', M are arranged in line, and in a position to abut against each other when the bolt G is fullydrawn back, as will be presently described; such insulation being of course'provided for the conducting-members carried by said bolts as will prevent any current passing along them when they are in com tact. The mode of operation is as follows: When all of the posts 6 are in their central position, and all the bolts G? have been moved into engagement (with the notches e by the springs g, the interlocking-circuit through the elements 28, g, g, 9 29, H, 30 31 and 42 will be closed, and the releasing-magnets H therefore will attract their several armatures'm, thus sever-j ally closin the circuits of the retractingmagnets I across the terminals mflm. As

soon as this takes place, said retracting! ma ets will be energized, and by attracting their armatures 9 will individually with draw the bolts G' from their several notches e, at the same time breaking the.

interlocking-circuit atgf, g.v The circuit of each retracting-magnet remains intact until its bolt. is withdrawn" -a sufficient distance to release the'post e; after which the bolt G continues to move back until by striking the end of the bolt M, the contact-piece m is moved away from the terminalsm, m, and

' the circuit of the retracting-magnet K thus broken. This action in turn releases the armature g, and the bolt G is driven forward again by the spring g, bfffin the meantime the post 6 having passed beyond its middle position, the bolt G rests against ,the side thereof ready for its next mterlocking movement.

From the above description itwill be readily seen that our invention is not limited to, spe'cial forms and mechanical constructions such as we have hereinaboveshown by way-of illustratiom'but that the principles thereof are expressible in a variety of ways i as will be well understood b electricians; therefore the scope of our claims isto be interpreted' in view of such alternative constructions.

Having thus described our invention what we claim as new'and des re to se'cure by Letters Patent is l. The combination of an alternatingcurrent'circuit, a direct-current circuit, a

service-circuit, a switch adaptedto connect said service-circuit with either of the other jcircuitsalternatively, an electromagneticdevice for operating saidswitch, said, electromagnetic-device being energized when ever current is turned into the alternatingcurrent circuit and de'nergized when there is no current therein, and said electromagnetic-device when energized acting tomove' said switch so as to connect s'aid service circuit with one of the other circuits and when deenergized with the other, and an Qelactrically-op'erated device acting automatically to hold said switch in the position corresponding to the energized position of said electromagnetic device and simultaneously cut oil current from thelatter so long as there is current in sa d alternating-current circuit, and torelease said'switch when the alternating-current is shut off from said circuit.

2; The combination of an alternating.-

icurrent circuit, a direct-current circuit, a

service-circuit, a switch having two positions in one of which said service circuitis break intercalated in the energizing 'cir-, cuit of said'electromagnetiddevice, an electromagnetic-device connected up with said alternating-current circuit and operating said make-and-break,'and a device arranged to mechanically engage and retain some 7 part movable withthe switch when the latter is'in the positioncorresponding to the energized condition ofsaid-first-named electromagnetic-device and simultaneously to cut oil current from the'latter,'.said engaging-device being operated'to move into, and being retained in its engaging position by the attraction of said second electromagnetic-device when energized, and being released therefrom when the latter is dee'nergi-zed. v ,v

3. The combination of an alternatingcurrent circuit, a direct-current circuit, a

service-circuit, a switch having two positionsin one of which said service-circuit is connected with sald alternating-currentcircuit and in the other with said direct-cur rent circuit, an electromagnetic-device op-- eratmg sald switch to shift it to one position or the other, and acting'when energized to move it into one of said positions and when deenergized into the other, a second electromagnetic-device, a mechanical-device operated by the attraction of said electromagnetic-device and adapted to mechaniswitch in the position corresponding tothe energized condition of said first-named electromagnetic-device. and to'hold it mechanically in said position, and two make-andcally engage some part connected with saidu breaks operated by said second electromagnetic-devic'e, and intercalated in series in the circuit of said first-named electromagnetic-device, one of said make-and-breaks being closed by the attraction of said second electromagnetic-device when the latter is energized, and opened when itis deenergized,

andthe other being closed when said mecal relation and governing electrically the movements of the respective switches; said interlocking-devices being adapted to prevent the shifting of any of said switches un-- less all' are shifted simultaneously.

5. The combination of an alternatingcurrent circuit, a direct-current circuit, oneor more service-circuits, a plurality of changeover-switches having each, two positions and connected with the service-circuits, so that in one position they .connect the latter to the alternating-current circuit and in the other to thedirect-current cir- 'cuit, a plurality of electromagnetic devices operating the respective switches and connected in circuit with a source of electrical energy, a second set of electromagnetic devices permanently connected to the alternating-current circuit and each actuating a make-and-break intercalated in the circuit of one of said firstnamed electromagnetic devices, and a plurality of interlockingelectrical devices connected up in joint electrical relation and governing the movements of the respective switches; said interlockingdevices being adapted to prevent the shifting of any of said switches unless all are shifted simultaneously.

6. The combination of an alternatingcurrent circuit, a direct-current circuit, one or more service-circuits, a plurality of changeover-switches having each two positions and connected withthe service-circuits so that in one positionthey connect the latter to the alternating-current circuit and in the other to the direct-current circuit, a set of electromagnetic devices operating the re spective switches and connected in circuit with'a source of electrical energy; a set of make-and-breaks intercalated in the circuit of the respective electromagnetic devices, a

' second set of electromagnetic devices permanently connected to the alternating-current circuit and each actuating one (it said make-andbreaks, a plurality of trip-devices normally disposed in the path of some part moving with said switches so as to prevent the shifting thereof. a plurality of elec trically-operated retracting-devices adapted each to retract one of said trip-devices so as to permit the shifting of said'switches, and an interlocking-circuit with which said retracting-devices are connected; said interlocking-circuit having -make-and-break points which are operated to effect the retracting of said trip-devices by said retracting-devices when and only when all of said switches are moved to the position at which they are checked by said trips.

7. The combination of an alternatingcurrent circuit, a direct-current circuit, one or more service-circuits, a plurality of changeover-switches having each two positions and connected with the service-circuits so that in one position they connect the latter to the alternating-current circuit and in the other to the direct-current circuit, a plurality of electromagnetic devices operating the respective switches and connected in circuit with a source of electrical energy, a set'of make-and-breaks intercalated in the circuit of the respective electromagnetic devices, a second set of electromagnetic devices permanently connected to the alternatingcurrent circuit-and each actuating one of said makeand-breaks, a plurality of tripdevices normally disposed in the path of some part moving with said switches so as to check them when in an intermediate pos tion, a plurality of retracting-devices adapted to withdraw the several trips-to permit the completing of the shifting-movement of said switches, a plurality of makeand-breaks which are operated by the several switches and closed when the latter are in said intermediate position, and an interlocking-circuit containing in series all of said make-and-breaks and all of said retracting-devices, whereby said interlockingcircuit is closed and said retracting-devices fall simultaneously,energized when and only when all of said switches are in said intermediate position.

8. The combination of an alternating-current circuit, a direct-current circuit, one or more service-circuits, a plurality of changeover-switches having each two positions and connected with the service-circuits, so that in one position-they connect the latter to the alternating-current circuit and in the other to the direct-current circuit, a plui-ality of electromagnetic devices operating the respective switches and connected in circuit with a source of electrical energy, a set of make-and-breaks intercalated in the circuit of the respective electromagnetic devices, a second set of electromagnetic deiice's. permanently connected to the alternating-current circuit and each actuating "one of said make-and-bi'eaks. a plurality i said position until said locking-devices are withdrawn from engagement therewith, a plurality of electrically-actuated retracting devices adapted to cause said locking-devices to be withdrawn 'under certain electrical conditions, an interlocking-circuit with which all of said retracting-devices are connected, and means actuated by said switches hen and only when they are all in said intermediate position forchanging the electrical conditions of said interlocking-circuit so as to cause said retracting-devices to retract the several locking-devices and thereby free all of said switches simultaneously.

of the respective electromagnetic devices, a

second set of electromagnetic devices permanently connected to the alternating-current circuit and each actuating one of said make-and breaks. a plurality of locking-devices automatically locking said switches in' an intermediate position whenever they are moved thereinto, said locklng-devices holding said switches in said position untilsaid.

locking-devices are withdrawn from engagement therewith. a plurality of electrically actuatedretracting-devices adapted to cause said locking-deviees'to be withdrawn under certain electrical conditions, a pluralltyof electrically operated releaslng-devices adapted to be actuated to bring about such condi-' tions. an inter]ocking-circuit with which all of said releasingclevices are connected, and make-and break devices operated by the movements of said switches and connected with said interlocking circuit so as to cause said releasing-devices to be actuated when and only when all of said switches are in their intermediate position. a

10. The combination of an alternatingcurrent circuit. a direct-current circuit, one or more service-circuits, a plurality of cliangeover-switches having each two positions and connected with the service-circuits so that in one position they connect the latter to the alternating-current circuit and in the other to the direct-current circuit, a plurality ot' clectronnignetic devices operating the respective switches and connected in the circuit with a source of electrical energy. a

ct of n1ake-andbreaks intercalated in the circuit of the respective electromagnetic-tie v \iccs. a second set ofelectromagnetic devicesf pcrrmrnentl y connected to the alternatin-g cu g rent circuit and each actuating one of said make-and-breaks, a plurality of locking-de vices automatically locking said switches in an intermediate position whenever' they are moved thereinto, said" locking-devices holding said switches in said position untilsaid locking-devices are Withdrawn from engagement therewith, a, plurality of electrically actuated retracting devices adapted to cause said locking-devices to be withdrawn under certain electrical conditions, a plurality of electrically operated releasing-devices adapted tobe actuated to bring about such conditions, an interlocking-circuitwith Which all of said releasing-devices are connected, and. make-and-break devices operated by the movements of said switches and connected with said interlocking circuit so as to cause said releasing-devices to be actuated when and only when all of said switches are in their intermediate position; said locking-devices being arranged so as after having fully re leased said switches to mechanically act upon said releasing-devices, and thereby break off the conditions which cause said lockingdevices to be retracted.

11. The combination of an alternatingcurrent circuit, a direct-current circuit, one or more service-circuits, a a plurality of changeove switches having each two posi-' tions and connected with the service-circuits so that inone position the'y connect the latter to the alternating-current circuit andin the other to the direct-current circuit, a plurality of electromagnetic devices operating. the respective switches and connected in circuit with a source of electrical energy, a set of make-and-breaks interca'lated in the circuit of the respective electromagnetic devices,

.asecond set of electroniagntic-devices permanently connected' to the alternating-current circuit and eachactuating one of said make-and-breaks, a second set of electromagnetic devices'permanently connected to the alternating-current circuit and each actuating one of said make-and-breaks. a plurality of locking-devices by. which said switches are respectively automatically engaged and held as they shift when in their intermediate positions, a plurality of electrically operated retracting-devices adapted to retract said locking-devices when energized, means for independently energizing the several retracting-devices, a plurality of make-and-break devices inserted in'the circuits of the several releasing-devices so that the latter are energized when said makeand-break devices are closedand deenergized when they are open, a pluralityof electrically operated releasing-devices adapted to close said make-and-breaks when energized, a second set of make-and-breaks each of which is closed byone of said locking-devices when in the locking-position andopened when retracted, and an interlocking-circurrent circuit, a direct-current circuit, one.

or more service-circuits, a plurality of changeover-switches having each two positions and connected with the service-circuits so that in one position they connect the latter to the" alternating-current circuit and in the other to the direct-current circuit, a plurality of electromagnetic-devices oper- ,ating the respective switches. and connected retracting-devices adapted to retract said,

locking-devices when energized, means for independently energizing the several retracting-devices,'a plurality of 'make-and-break devices inserted in the circuits of the se v-' eral releasing-devices sothat the latter are energized when. said make-and-break devices are closed anddeenergized when they are open, a plurality of electrically operated releasing-devices, adapted to close said makeand-breaks when energized. a second set of make-and-breaks each of which is closed by one of said locking-devices whenin the locking-position and opened when retracted, and an interlocking-circuit containing all of said second set of make-and-breaks and all of said releasing-devices in series whereby the latter are energized to close said first set of make-and-breaks andthereby energize the retracting-devices only when all of said switches are in their intermediate positions; said locking-devices being arranged in their attracting movements after they have completely released said switches to mechanicallv actupon said first set of make-andbreaks so as to open the same, thereby again releasing said locking-devices and permitting them to take up a position ready for locking said switches when the latter shall again come into their intermediate positions.

13. The combination of an alternating which said service-circuits are connected with said alternating-current circuit and in the other with said direct-current circuit, a set of electromagnetic devices operating said. switches to shift them into one position or the other and acting when energized to move them'into one of said positions and when de'einergized into the other, a second set of electromagnetic devices, a set of mechanical-devices operated by the attraction of the respective -electromagnetic devices of the second set and associated with the respective switches and adapted to mechanically engage some part connected with the latter in the position corresponding to the energized condition of the first-named set of electromagnetic-devices to hold them mechanically in said position, a set'of makeand-breaks associated by pairs with the respective electromagnetic devices of the second set and operatedthereby, each pair being intercalated inseries in the circuit of the corresponding electromagnetic device of the first set, one of each pair being closed by the attraction of the electromagnetic device of the'second set when the latter is energized and opened when it is deenergized, and the other being closed when said mechanically engaging device is in the disengaging position, and opened when it is. in the engaging position; a plurality of locking-devices by which said switches arerespectively automatically engaged and held as they shift'when in their intermediate positions, a plurality of electrically operated retracting-devices adapted to retract said locking-devices when energized, means for independently, energizing the several retracting-devices, a plurality of make-andbreak devices inserted in the circuits of the several retracting-devices so that the latter are energized when saidxmake-and-break devices are closed and deenergized when they are open, a plurality of electrically operated releasing-devices adapted to closet said make-and-breaks when energized, a second set of make-and-breaks each of which is closed by one of said locking-devices when in the locking-position and opened when retracted, and an interlocking-circuit containing all of said second set of make-andbreaks and all of said releasing-devices in series whereby the latter are energized to close said first set of make-and-breaks and thereby energize the retracting-devices only when all of said switches are in their intermediate positions.

In witness whereof we have hereunto set our. hands in presence of two witnesses.

JULIUS H. GUGLER. GEORGE W. COLLES. Witnesses:

HARRY J. MILTON, Ms. C. PETERSON. 

